SCALE AND HARMONY
Accompanying tunes and songs
Scottish traditional music is essentially melodic and monophonic - it is rooted in unaccompanied tunes and songs. The only kinds of harmony that exist naturally are the drone, as with the drones of the bagpipes, and the heterophony (simultaneous variations of a melodic line) of the call-and-response style psalm singing of some Gaelic-speaking presbyterian churches, as you can hear in archive recordings
Harmonic backing of melodies, particularly dance tunes, evolved during the late 18th century, when instruments such as the cello and different keyboard instruments were used to accompany dance tunes, especially in polite society.
The concept of a 'band' of different instruments and singers playing tunes and songs together with harmonic accompaniment is very much a modern concept, and evolved during the British folk revival of the 1950s and 60s. Many Scots were significant figures in the folk revival including Bert Jansch, Hamish Henderson and Ewan McColl, who was born in Salford of Scottish parents.
Folk and traditional music has absorbed many influences over the years since then, especially the different forms of popular music that have been in fashion at different times. For instance, in the late 1960s and 70s, many folk-rock bands emerged throughout Britain and Ireland such as Fairport Convention, Horslips in Ireland and Runrig in Scotland.
A note on scales and modes
You will be familiar with at least two seven-note musical modes - the major and minor modes. Scottish traditional music and song uses many different scales, mostly five (pentatonic), six (hexatonic) and seven-note scales. Each scale has a different musical colour and you can find them easily by starting on different notes on the white-note range of a piano or keyboard.
If you start on C and play C, D, E, F, G, A, B, this gives you the major mode, which is also known as the Ionian mode. The song 'Happy Birthday' is in the major mode, using all seven notes of the scale. But if you start on G and play G, A, B, C, D, E, F, G, you get a different scale with a flattened seventh note - this is known as the mixolydian mode. Bagpipe chanters are all tuned to the mixolydian mode - (low G), A, B, C#, D, E, F#, G, A. Starting on other notes and playing a white-note scale on the piano can show you the various other seven-note modes.
Hexatonic and pentatonic scales are also sometimes known as 'gapped scales', although that suggests that there is something missing. This is not the case; these scales simply have only five or six notes rather than seven. You can play a hexatonic scale by starting on C and playing C, D, E, F, G, A, C.
Pentatonic scales can be found in different kinds of traditional music all over the world. For instance, if you listen to some Native American or Mongolian songs, you might think that you were hearing something very familiar - this is because they are in a pentatonic scale. The easiest way to find the note of the different pentatonic scales is to play the black notes of a keyboard. Try playing D♭, E♭, G♭, A♭, B♭. Now think of the tune of the 'Skye Boat Song' - this is the scale that the song is sung in.
There are many other different scales and modes. Pentatonic tunes are very common in Scotland and in many other countries as well.
Western scales usually have seven notes, such as the scale of C major, which runs C, D, E, F, G, A, B. The pentatonic scale has only five notes. When starting on C, the pentatonic scale runs C, D, E, G, A. The notes F and B are not used.
The pentatonic scale can start on any note. An easy way to work out the pentatonic scale is to play on the five black notes of the piano. If you can play a tune using only the black notes, then the tune you are playing is pentatonic.
'The Skye Boat Song' and 'Auld Lang Syne' are both examples of pentatonic tunes.